Ohio researchers create new type of coating for solar panels

Researchers at Case Western Reserve University developed a new type of coating that could make the photovoltaic cells used to make solar panels last six times longer.

This development could dramatically decrease the cost of replacing worn out cells, according to a release from the university.

The project was a collaboration between Case Western Reserve University, in Cleveland, and the University of Rochester, in New York.

Guiseppe Strangi, a professor of physics at Case Western Reserve University, and his collaborators created a coating made from a 15 nanometer-thick film of germanium. The new coating could solve a major issue facing the solar energy industry, Strangi said.

Photovoltaic panels produce energy efficiently during the day, when the sun is out and demand is relatively low. The panels aren’t as good when the sun sets and demand goes up, when families are home from work and school. On top of that, storing energy from photovoltaic panels is expensive.

The new optical coating can both reflect and transmit the same wavelength of light. This is a big deal because, for more than a century, optical coatings have been able to do one or the other, not both. 

The coating could be fine-tuned to reflect the optimal wavelength and absorb the rest of the solar spectrum. That means the panels could transfer those wavelengths to heat; storing thermal energy is much cheaper than storing electricity.

Strangi said this approach would also protect the photovoltaic cells from overheating, which would make them last much longer. 

Using the coatings in solar panels will take some time to develop, but it’s just one potential use for the coating. The researchers call this new class of coatings Fano Resonance Optical Coatings, a nod to Italian-born American physicist Ugo Fano.

Strangi worked on the project with Mohamed Elkabbash, a Case Western Reserve University alumnus who is now a post-doctoral researcher at MIT, Mike Hinczewski, associate professor of physics at Case Western Reserve University and Chunlei Guo, professor at Rochester’s Institute of Optics.

Their full findings can be found in the journal Nature Nanotechnology.